What is the Check Engine Light?
Written by Lee Wyatt (last updated May 28, 2010)
You might be surprised, but one of the more common questions that I have heard asked by first time vehicle owners (and some not so first time car owners) is "what is the check engine light?"
There is a technical answer to this question that goes something like this. These lights are a visual indicator of your vehicle's on-board computer of a malfunction that was sensed in one of the monitored systems. Basically, this is your car's way of saying, "Hey, look at me! There's something wrong here!" And it's for this reason that I like to collectively call these lights the idiot lights, because (jokingly, I assure you) you would have to be an idiot to miss them when they come on.
Below is a brief list of the different lights, and what they mean.
• Engine Service Light. This light can either be the actual words "Service Engine Soon," or a small picture of what looks like an engine. When this lights up it typically means that there is a problem somewhere in the engine itself, and that it needs to be looked at. Usually this is going to be something with the Electronic Control Module (ECM) which is designed to monitor your vehicles emissions. To know for sure what the problem is, have it looked at by your mechanic.
• Thermometer. When something that looks like a thermometer lights up, it means that your vehicle is running too hot. Pull over, and let the vehicle cool down. Check your coolant levels to ensure that they are at the proper levels. If they are, have the vehicle looked at by a mechanic. If not then replace and check again.
• Battery. If a light comes on that looks like a battery, that means that you battery level is getting low or that there is a drop in the amount of battery output. Check the connections on your battery and if they are free of corrosion and properly seated then you should take your vehicle to a mechanic.
• Gas Pump. This light is only going to come on when you are running out of gas. To make it turn off, simply add more gas.
• Oil Can. When the oil can comes on that means that there is something wrong with your engine's oil. The simplest (and most common) reason for this to come on is that you are running low on oil, so simply refill to the proper level, and your light should go off.